lisp/isearch-multi.el

   1 ;;; isearch-multi.el --- isearch extensions for multi-buffer search
   2
   3 ;; Copyright (C) 2007, 2008  Free Software Foundation, Inc.
   4
   5 ;; Author: Juri Linkov <juri@jurta.org>
   6 ;; Keywords: matching
   7
   8 ;; This file is part of GNU Emacs.
   9
  10 ;; GNU Emacs is free software; you can redistribute it and/or modify
  11 ;; it under the terms of the GNU General Public License as published by
  12 ;; the Free Software Foundation; either version 3, or (at your option)
  13 ;; any later version.
  14
  15 ;; GNU Emacs is distributed in the hope that it will be useful,
  16 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 ;; GNU General Public License for more details.
  19
  20 ;; You should have received a copy of the GNU General Public License
  21 ;; along with GNU Emacs; see the file COPYING.  If not, write to the
  22 ;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  23 ;; Boston, MA 02110-1301, USA.
  24
  25 ;;; Commentary:
  26
  27 ;; This file adds more dimensions to the search space.  It implements
  28 ;; various features that extend isearch.  One of them is an ability to
  29 ;; search through multiple buffers.
  30
  31 ;;; Code:
  32
  33 ;;; Search multiple buffers
  34
  35 (defgroup isearch-buffers nil
  36   "Using isearch to search through multiple buffers."
  37   :version "23.1"
  38   :group 'isearch)
  39
  40 (defcustom isearch-buffers-multi t
  41   "Non-nil enables searching multiple related buffers, in certain modes."
  42   :type 'boolean
  43   :version "23.1"
  44   :group 'isearch-buffers)
  45
  46 (defcustom isearch-buffers-pause t
  47   "A choice defining where to pause the search.
  48 If the value is nil, don't pause before going to the next buffer.
  49 If the value is `initial', pause only after a failing search in the
  50 initial buffer.
  51 If t, pause in all buffers that contain the search string."
  52   :type '(choice
  53           (const :tag "Don't pause" nil)
  54           (const :tag "Only in initial buffer" initial)
  55           (const :tag "All buffers" t))
  56   :version "23.1"
  57   :group 'isearch-buffers)
  58
  59 ;;;###autoload
  60 (defvar isearch-buffers-current-buffer nil
  61   "The buffer where the search is currently searching.
  62 The value is nil when the search still is in the initial buffer.")
  63
  64 ;;;###autoload
  65 (defvar isearch-buffers-next-buffer-function nil
  66   "Function to call to get the next buffer to search.
  67
  68 When this variable is set to a function that returns a buffer, then
  69 after typing another \\[isearch-forward] or \\[isearch-backward] \
  70 at a failing search, the search goes
  71 to the next buffer in the series and continues searching for the
  72 next occurrence.
  73
  74 The first argument of this function is the current buffer where the
  75 search is currently searching.  It defines the base buffer relative to
  76 which this function should find the next buffer.  When the isearch
  77 direction is backward (when `isearch-forward' is nil), this function
  78 should return the previous buffer to search.  If the second argument of
  79 this function WRAP is non-nil, then it should return the first buffer
  80 in the series; and for the backward search, it should return the last
  81 buffer in the series.")
  82
  83 ;;;###autoload
  84 (define-minor-mode isearch-buffers-minor-mode
  85   "Minor mode for using isearch to search through multiple buffers.
  86 With arg, turn isearch-buffers minor mode on if arg is positive, off otherwise."
  87   :group 'isearch-buffers ;; :lighter " X"
  88   (if isearch-buffers-minor-mode
  89       (progn
  90         (add-hook 'isearch-mode-hook 'isearch-buffers-init nil t)
  91         (set (make-local-variable 'isearch-search-fun-function)
  92              'isearch-buffers-search-fun)
  93         (set (make-local-variable 'isearch-wrap-function)
  94              'isearch-buffers-wrap)
  95         (set (make-local-variable 'isearch-push-state-function)
  96              'isearch-buffers-push-state))
  97     (remove-hook 'isearch-mode-hook 'isearch-buffers-init t)
  98     (kill-local-variable 'isearch-search-fun-function)
  99     (kill-local-variable 'isearch-wrap-function)
 100     (kill-local-variable 'isearch-push-state-function)))
 101
 102 (defun isearch-buffers-init ()
 103   "Set up isearch to search multiple buffers.
 104 Intended to be added to `isearch-mode-hook'."
 105   (setq isearch-buffers-current-buffer nil))
 106
 107 (defun isearch-buffers-search-fun ()
 108   "Return the proper search function, for isearch in multiple buffers."
 109   (lambda (string bound noerror)
 110     (let ((search-fun
 111            ;; Use standard functions to search within one buffer
 112            (cond
 113             (isearch-word
 114              (if isearch-forward 'word-search-forward 'word-search-backward))
 115             (isearch-regexp
 116              (if isearch-forward 're-search-forward 're-search-backward))
 117             (t
 118              (if isearch-forward 'search-forward 'search-backward))))
 119           found buffer)
 120       (or
 121        ;; 1. First try searching in the initial buffer
 122        (let ((res (funcall search-fun string bound noerror)))
 123          ;; Reset wrapping for all-buffers pause after successful search
 124          (if (and res (eq isearch-buffers-pause t))
 125              (setq isearch-buffers-current-buffer nil))
 126          res)
 127        ;; 2. If the above search fails, start visiting next/prev buffers
 128        ;; successively, and search the string in them.  Do this only
 129        ;; when bound is nil (i.e. not while lazy-highlighting search
 130        ;; strings in the current buffer).
 131        (when (and (not bound) isearch-buffers-multi)
 132          ;; If no-pause or there was one attempt to leave the current buffer
 133          (if (or (null isearch-buffers-pause)
 134                  (and isearch-buffers-pause isearch-buffers-current-buffer))
 135              (condition-case nil
 136                  (progn
 137                    (while (not found)
 138                      ;; Find the next buffer to search
 139                      (setq buffer (funcall isearch-buffers-next-buffer-function
 140                                            buffer))
 141                      (with-current-buffer buffer
 142                        (goto-char (if isearch-forward (point-min) (point-max)))
 143                        (setq isearch-barrier (point) isearch-opoint (point))
 144                        ;; After visiting the next/prev buffer search the
 145                        ;; string in it again, until the function in
 146                        ;; isearch-buffers-next-buffer-function raises an error
 147                        ;; at the beginning/end of the buffer sequence.
 148                        (setq found (funcall search-fun string bound noerror))))
 149                    ;; Set buffer for isearch-search-string to switch
 150                    (if buffer (setq isearch-buffers-current-buffer buffer))
 151                    ;; Return point of the new search result
 152                    found)
 153                ;; Return nil when isearch-buffers-next-buffer-function fails
 154                (error nil))
 155            (signal 'search-failed (list string "Repeat for next buffer"))))))))
 156
 157 (defun isearch-buffers-wrap ()
 158   "Wrap the multiple buffers search when search is failed.
 159 Switch buffer to the first buffer for a forward search,
 160 or to the last buffer for a backward search.
 161 Set `isearch-buffers-current-buffer' to the current buffer to display
 162 the isearch suffix message [initial buffer] only when isearch leaves
 163 the initial buffer."
 164   (if (or (null isearch-buffers-pause)
 165           (and isearch-buffers-pause isearch-buffers-current-buffer))
 166       (progn
 167         (switch-to-buffer
 168          (setq isearch-buffers-current-buffer
 169                (funcall isearch-buffers-next-buffer-function
 170                         (current-buffer) t)))
 171         (goto-char (if isearch-forward (point-min) (point-max))))
 172     (setq isearch-buffers-current-buffer (current-buffer))
 173     (setq isearch-wrapped nil)))
 174
 175 (defun isearch-buffers-push-state ()
 176   "Save a function restoring the state of multiple buffers search.
 177 Save the current buffer to the additional state parameter in the
 178 search status stack."
 179   `(lambda (cmd)
 180      (isearch-buffers-pop-state cmd ,(current-buffer))))
 181
 182 (defun isearch-buffers-pop-state (cmd buffer)
 183   "Restore the multiple buffers search state.
 184 Switch to the buffer restored from the search status stack."
 185   (unless (equal buffer (current-buffer))
 186     (switch-to-buffer (setq isearch-buffers-current-buffer buffer))))
 187
 188 (provide 'isearch-multi)
 189
 190 ;; arch-tag: a6d38ffa-4d14-4e39-8ac6-46af9d6a6773
 191 ;;; isearch-multi.el ends here